Apparatus and its method of multiplexing optic signal hybrid fiber coaxial network

An optical transceiving device having a multiplexing function in an HFC(Hybrid Fiber Coaxial) network and a method thereof are provided to transmit downstream signals only to every sub cell by using high-availability frequency bands of an optical cable network, thereby remarkably improving transmission efficiency and application of network resources. A photoelectric converter(321) converts optical signals, where coaxial cable available frequency band signals and downstream channel signals more than coaxial cable available frequency bands are combined with each other, into electric signals. A downstream signal processor(322) individually separates the downstream channel signals to frequency down-convert the separated signals, and combines the down-converted downstream channel signals with the coaxial cable available frequency band signals converted into the electric signals, then outputs the combined signals sub cells within a coaxial cable. An upstream signal processor(323) up-converts upstream signals received from the plural sub cells into different frequencies within coaxial cable available frequency bands, and combines the up-converted signals. An electro-optic converter(324) converts the combined and multiplexed upstream signals into optical signals, and sends the optical signals through an optical cable network.